American Stoneseed

Lithospermum latifolium Boraginaceae

Other names

American Gromwell

Growth habit

Herbaceous

Perennation

Perennial

Native distribution

Native to the Finger Lakes Region

Cultivation

Prefers rich, calcareous forest soils. Moist to dry.

Propagation

White stone-like nutlets surrounding the seeds are so hard it is difficult for the seeds to germinate without scarifying. Has a double or triple dormancy.

Climate change sensitivity

Over the period from 1986 to 2015, Lithospermum latifolium bloomed an average of 16 days earlier.

Location

Mundy Wildflower Garden

Source of plant

Unknown

Description

This perennial plant is about 1½“2½' tall, branching occasionally. The stems are light green and densely covered with white hairs. The alternate leaves are up to 5½" long and 2" across; they are lanceolate to ovate, smooth along the margins, and sessile. The upper surface of each leaf is dark green, sparsely covered with short hairs, and pinnately veined; the lower surface is light green and densely covered with short white hairs. The lateral veins are conspicuous on both sides of the leaves. The flowers bloom near the apex of the stems. They occur individually from the axils of the leaves; their pedicels are short. Each flower is about ¼" across, consisting of a hairy green calyx with 5 linear-lanceolate teeth and a pale yellow corolla with 5 spreading lobes and a narrow throat. The tube of the corolla is no longer than the teeth of the calyx. The reproductive organs are hidden within the corolla. The blooming period occurs from mid-spring to early summer. Only a few flowers are in bloom at the same time. They are replaced by ovoid-globoid nutlets with an outer coat that is white, smooth, and hard. The root system consists of a taproot, which may send up more than one s

USDA Hardiness Zone

3

Special characteristics

A rare native plant that naturally occurs in the Mundy Wildflower Garden.

Status

L2|S2|G4